package main

import "fmt"

//hash表:36ms 38%,5.3MB 18%
func firstUniqChar(s string) byte {
	sMap := make(map[rune]int)
	for _, v := range s {
		sMap[v]++
	}
	for _, v := range s {
		if sMap[v] == 1 {
			return byte(v)
		}
	}
	return ' '
}

func main() {
	fmt.Println(firstUniqChar("dsdsd"))
}
